Transplantation of a graft organ or tissue from a donor to a host patient is a feature of certain medical procedures and treatment protocols. Despite efforts to avoid graft rejection through host-donor tissue type matching, in transplantation procedures where a donor organ is introduced into a host, immunosuppressive therapy is generally required to the maintain viability of the donor organ in the host. However, despite the wide use of immunosuppressive therapy, organ transplant rejection can occur.
Acute graft rejection (AR) of allograft tissue is a complex immune response that involves T-cell recognition of alloantigen in the allograft, co-stimulatory signals, elaboration of effector molecules by activated T cells, and an inflammatory response within the graft. Activation and recruitment of circulating leukocytes to the allograft is a central feature of this process. It is important to understand critical pathways regulated in AR, and if there are intrinsic similarities in the rejection molecular mechanisms across different solid organ transplants (e.g., kidney, heart, liver, lung, intestine, pancreas, etc.).
Early detection of AR is one of the major clinical concerns in the care of transplant recipients. Detection of AR before the onset of graft dysfunction allows successful treatment of this condition with aggressive immunosuppression. It is equally important to reduce immunosuppression in patients who do not have AR to minimize drug toxicity.
Accordingly, techniques for monitoring for an AR response in a transplant recipient, including predicting, diagnosing and characterizing AR, are of interest in the field. The present invention meets these and other needs.